Process and apparatus for producing sheet glass



J. L. DRAKE May 24, 1932.

PROCESS AND APPARATUS FOR PRODUCING SHEET GLASS Original Filed Nov.- 50 1926 K i T fliJNIrEo- STATE-S PATENT 4 Patented May 24, 1932 Joni: n. DRAKE, oF ToLEno, oHIo, ASSIGNOR ToniBBEir-ows tsroanfetass dom sz, oFToLEDo, 051m, A oo'RPonaTion-or oHIo j apparatus.

PRocEss AND APPARATUS roizt raonuomesnniir eLAss Substitute for application Serial No.

The present invention relates to sheetfglass mportant object of the inventioniisto provide, in sheet glass apparatus, means. for 'forming'a sheet under pressure.

A further .ob'ect of th1s invention is to provide anapparatus of this nature wherein a sheet is continuously and positively drawn downwardly from a source of molten glass Another object of the. invention isto pr v vide an apparatus for producing sheet glass wherein asheet of glass may be continuously drawn from a sourceof molten glass, the source being supported on an air cushlon. 1 Another object of the invention is to provide sheet glass forming apparatus wherein a sheet is drawn downwardly from a source of molten glass which is constantly urged in a direction opposite to the dra wof the sheet. n y

A still further object of the invention is to produce sheet glass-by drawing sheet from a mass of molten glass while mainta ning an air pressure inlsurrounding relatlon to the sheet during its formative period. I 7 Another object of the invention is tel-provide an apparatus of this naturewhereln a sheet of glass is drawn downwardly from a molten mass, thesheet being formed in a compartment having an air pressure therein, said sheet being cut transversely of ts length and removed from sald compartment in a manner that the pressure therein will not bedisturbed. l I

' Other objects and advantagesofttheinvention willbecome moreapparent during the course of the following description. In the. drawings wherein like numerals are employed todesignate like parts through-- out the same; ",Fig. 1 is a vertical longitudinal section through a sheetglass forming apparatus constructedin accordance with the present invention, 1 I Fig. 2 is an enlarged sectional detail of a portion of the machine, and' U Fig/31s afragmentaryverticalJlongitudinal sectionthrough a slightly modified "form of construction. I

In the drawings," he 5 designates a .atiornlfilt will be seenthatany thickness of vsl ee't'can be produced as the'rolls 16 are mov} Y 151,672, filed noveinber 36,1926. {This application-filed Novemberm, I v -1930; Ser ia11\To.494,6'7;5. r

tank furnace containing a: mass of] molten V glassb." The numeral "(designates a boot or draw receptacle which is continuously supplied with molten glass'f'rom the in ate-5.

The bottom of the'receptaolef'iis provided.

with a transverse slotv having depending therefrom lips or slabs 8 Arranged around the'receptacle 7 is a spaced wall 9'forming a compartment 10 which may be heated f to; properlycontrol the temperature oftheglass insaid receptacle. Heating means 11 may be associated with the compartment 10. a Y

. sheet 12 is adapted' to be continuously .1 drawn downwardly from the source 13 dise a posedbetween the spaced'lips or downwardly extendingprojections 8.. Arrangedaround the "sheet is a housing flt-formingaclosed compartment, the upper endjof the housing being-associated withthe lips 8 in a manner tha'tan air -tightjointiis hadf Arrangdwithin the housing l l is a plu-f ralzity of preferably stationary rotatable rolls 15, and cooperatingwith the stationaryjrolls 15am preferably adjustable rotatable rolls 16. Each of the rolls 16-.may be carried by suitable brackets 17 pivoted as at 18. l/Veightsl 19 may be; associated with theendsfofthe arms 17in a. manner that the rolls will be normally urgedtowardlthestationary rolls V V so roll lb-is carried; by the. shaft 17 extending In Fig. 2 is shown affragmentary.detail of j the method of niountingthe rolls within the j housing; isshown, a suitable (flange 20 I may be carried by the housing wallsla. The I 7 outwardly through thefiangefQO .and jo'urnaledFin' a suitable bushing. 21; .Afpacking naterial QQ'may be ,interposed 'between the end of thebushing 21 and 1thefwall' of the be formed for the shaft.

housing. 1 1 so that an air-tightbearingiyvill willnotbe injured during the drawing ope'r 1 At east some. of therolls 15 androlls 16 are positively driven and'are adapted to consatay draw thesheet "12 from itssourcelil. The rolls are preferably; formed fromflsuch. inaterial as asbestos or aform of nonfcorrosive metal so that thesu'r'fa ces oftheysheet.

1 sufficiently heavy to cause the rolls to remain able about their pivots 18, the weights being in contact with the sheet being produced, but

not sufficiently heavy to cause an 1n urious pressure upon the sheet.

Arranged at the bottom of the housing 14 is a transfer mechanism. The sheet,-in itsdownward movement,is out transversely pf its line of draw'by a cutting mechanism 11- lustrated diagrammatically and designated by the numeral 23. Asuitable guide rollQL 7 may be provided within the housing and adapted to contact with the sheet'as illustrated in Fig. 1. It will be seen that a'group of a pressure is set up and maintained within A constant pressure within the compartment rolls, numbered 25, is arranged at the bottom of the housing 14. These rolls are driv on relatively. faster than the upper rolls 15 and 16- so that astliesh'eet passes therebetween they will be carriedaway relatively faster,

'- making the gap between the cut sheet and its succeeding-sheet comparatively great. The sheet is preferably transferred by the mech anism designated in its entirety by the numer-- al 26, so that the interior of the housing surrounding the sheet will not be affected. As

is' shown, the transfer mechanism 26 comprises two compartments 27 and 28.respecthe sheet 32 will have passed completely into the compartment'27. The transfer mechanism is then shifted to a position illustrated in dotted lines so that the compartment 27 willregister withthe other openings. 30, and

as the sheet 32 is passing from the compartment 27, another sheet will be passing into the compartment 28. v V

In accordance with the present invention the housing 14, and to accomplish thisa suitable pressure supply reservoir 33may be supplied. The pressure supply reservoir has con- -nection by means of the pipe 34 and valve 35 to a suitable pressure means. To permit a formedby'the housing 14, a conduit 36 connects reservoir .33 and housing 14. The bell 37 floats in a sealing means.38. The pressure means used is preferably air which may be heated or not as desired.

7 By the pressure means illustrated, or its equivalent, a pressure is created within the compartment surrounding the sheet 12,v the pressure being such that'thehead pressure "of the source of moltenglass 13 will be "preferablycounteracted so that the sheet 12' canbe positively drawn fromsits source instead of flowed therefrom. By positively drawing the sheet downwardly in this man-e ner, a more uniform thickness and flatness of sheet can be had, as the p'ressure'w-ill' offer the necessary resistance required." As the pressure is constant, there will be no tendency to-' ward thick and thin spots in the sheet. By means of the transfer mechanism set forth, the

finished sheets of glass can be handled without interruption to the pressure within the compartment.

In Fig.3, endless conveyors 39 are used instead of the rolls 15 and 16.

The pressure in the housing is such that the sheet source will'be urged in'a' direction opposite to the direction of draw ofthe'sheet;

In other words, the pressure will overcome gravity,-and thus prevent a fiowing of'the feature is entirely different than thepr'inciple upon which the prior art structures are based.

Heretofore, machines have been designed to permit a downward flow of glass, but due to differences in viscosity of the glass, flowing of glass downwardly is not satisfactory.

The glass sheet is also preferably annealed in the compartment before it enters into the transfer mechanism; As the compartment formed by the housing 14 is vertical, the hot-, test airwill beat the top and will naturally become progressively cooler as the bottom of said compartmentis approached. This condition makes said compartment an ideal annealing chamber. Supplementary heating or cooling means canbe employed to control the temperature around the sheet.

I It is to be understood that the form of the invention herewith shown and described is to be taken as the preferred embodiment of the same, and that various changes in the shape, sizeand arrangement of parts may be resorted to without departing from the subj oined claims.

Claims:

spirit of the invention o'r'the scope of the containing a source of molten glass, means for drawlng 'a sheet downwardly therefrom,

'L-In sheet glass apparatus, areceptacle and'a gaseous fluid for exerting a pressure against said source, in a direction opposite to the movement of'theshjeet of glass, said pressure being sufiicierit to support the, sheet source.

2. In sheet glass apparatus, a receptacle contaimng a' source of molten glass, means i for drawing a sheet downwardly therefrom, V I and means for supportingsaid source on a y cushion of gaseous fluid 3. In. sheet glass apparatus, a receptacle containing asource ofmolten glass, means;

for drawing a sheet downwardly therefrom,

a housing arrangedflaround the sheet, and

means for creating a pressure within said glass, but on the other hand will make it necessary to positively draw thesheetf This housing, said pressure being suificient to support the sheet source. I

4. In sheet glass apparatus, a receptacle containing a source of molten glass, means 7 for continuously and positively drawing a sheet downwardly therefrom, means for forming a'closed compartment around said source and sheet, and means for automaticale ly maintaining a uniform predetermined gaseous fluid pressurewithin and throughout said compartment.

5. In sheet glass apparatus, a receptacle containing a source of molten glass, means for continuously and positively drawing a sheet downwardly therefrom, means for forming a closed compartment around said source and sheet, and means for automatically maintaining a predetermined gaseous fluid pressure within said compartment, the gaseous fluid pressure being such as to sup port the sheet source. a p

6. In sheet glass apparatus, a receptacle containing a source of molten glass, means for drawing a sheet downwardly therefrom, means for forming a closed compartment around said source and sheet, means for creating a gaseous fluid pressure within said compartment great enough to support said sheet source and means for. removing the sheet from said compartment without (11S- turbing the gaseous fluid pressure therein.

7. In sheet glass apparatus, a receptacle containing a source of molten glass, means for drawing a sheet downwardly therefrom, means for forming a closed compartment around said source and sheet, means for creating a gaseous fluid pressure within said compartment great enough to support said sheet source, means for removlng the sheet from said compartment without disturbing the gaseous fluid pressure thereln, and means for cutting the sheet transversely of its length.

8. The process of producing sheet glass,

consisting in supporting a source of molten glass on a gaseous fluid cushion, and then drawing a sheet therefrom.

9. The process of producing sheet glass, consisting in supporting a mass of molten glass on a gaseous fluid; cushion, and their drawing a sheet'downwardly therefrom.

. v Signed at Toledo, in the county of Lucas and State of Ohio, this 7th day of November, 1930.

J OHN DRAKE. 

